It's especially dangerous in trap handlers since the return value of the
function becomes the return value of the last command before the trap,
not the last command in the current function. This applies to any
function executed in a trap handler, nested functions included.
In one case, install_packages failed (via return 14), which was inside a
conditional that then ran exit 14, which triggered the EXIT handler,
which called clean_up, which called remove_deps, which had !RMDEPS and
thus returned. The return value of remove_deps became the return value
of install_packages, triggering the ERR handler, which (due to another
problem) was still the user function handler, which then printed a
misleading error message and overrode the exit code with 4.
Signed-off-by: Allan McRae <allan@archlinux.org>
05a3641c76